PiFM spectra generally replicate conventional IR spectra recorded from bulk samples, shown in this example of polyethersulfone (PES). Occasionally, slight shifts in peak wavenumber and amplitude are observed in PiFM spectra, arising from the extreme sensitivity of PiFM to localized populations of molecules. One strength of the PiFM method is capturing the behavior of materials […] Read more
The chemical mapping capability of PiFM is demonstrated in an asphalt sample containing multiple related components. Note in the accompanying spectra that the signal strength for maltene is lower than asphaltene except at ~1501 cm-1 (shown in dotted circles on both PiFM and FTIR spectra). This small difference is easy to overlook until rendered in […] Read more
Photo Physics PiFM captures ultra-confined resonances and local field enhancement in hexagonal boron nitride optical nano-dipole antennae. Unlike s-SNOM, PiFM works by mechanically detecting the gradient of the optical force generated by near fields on the AFM tip without the need for optical detection. The technique images the z-component of the field, which has the […] Read more
These transparent conductors are composed of silver nanowires embedded in clear plastic. AFM topography (left) displays those nanowires that contribute to surface morphology. However, buried nanowires do not appear in topographic images. PiFM imaging (right) does reveal the placement of embedded nanowires by taking advantage of the enhancement of the overlying acrylate polymer signal (1745cm-1) […] Read more
We recently imaged another t-BOC chemically amplified photoresist. Last time, the contrast between the exposed and unexposed regions were not as striking since we used the same peak at 1760 cm-1 to image (see blog post: Latent Images of Exposed EUV Photoresist.) This one actually uses a peak that shifts by 6 cm-1 to create a very […] Read more
Can you recognize this painting? We can’t either from a one micron scan, but we do know that these images expose different chemical components found in a tiny piece of an oil painting. The formation of soap aggregates is of growing concern to art conservation and restoration, especially in traditional 15th to 20th century oil […] Read more
We develop a new technique called photo-induced force microscopy (PiFM), which allows us to image the chemical makeup of samples with extremely high spatial resolution. We spent some time to image isolated protein particles and obtained results that may be consistent with the design of the protein cage. A Single Self-assembled Icosahedral Protein Cage Imaged […] Read more
A new PiFM application paper showing FTIR spectra, PiFM and PiFM+topography images of a polymer solar cell (PSC) with thermal annealing treatment was published in “Nature Communications” by Chenkai Sun, Zhi-Guo Zhang and Yongfang Li, “A low cost and high performance polymer donor material for polymer solar cells.” (doi:10.1038/s41467-018-03207-x) PiFM measurements were taken by William Morrison from Molecular […] Read more
Episode 1: Nanoscale Silicon Strain Measurements – Silicon Oxide Stress Measurements. Photo-induced Force Microscopy – Series – PiFM @ Work presents the first in a series of video shorts from the Applications Lab at Molecular Vista. Episode 1: Nanoscale Silicon Strain Measurements explores silicon oxide stress using the Vista-IR microscope. Please subscribe to our Molecular Vista […] Read more
The development of EUV (extreme ultraviolet) resist materials is critical to producing semiconductor devices with the smallest feature sizes. Understanding the light-induced chemistry of EUV photoresist and its impact on the quality of EUV lithography would help engineers to optimize this important technology. Photo-induced Force Microscopy (PiFM), with its capability to detect nanoscale chemical properties, is well suited […] Read more
